Answer:
Parallel construction
Step-by-step explanation:
The parallel construction refers to sentences constructions that have two or more words, phrases or clauses that are grammatically similar or identical in their structure. It is often used to show that the ideas with the same grammatical form (or structure) are equally important, to give a natural flow to the reading and to make it easier to process.
The sentence "We found the seminar interesting, entertaining, and inspiring" is an example of this construction because it uses the same "-ing" verbs to describe the seminar: interesting, entertaining, and inspiring.